1. Field of the Invention
The present invention relates generally to clamping devices and more particularly to a special purpose clamp having a pivotable jaw with an overcenter linkage for use in installing guard rail sections.
2. Description of the Prior Art
Typically, highway divider guard rails are comprised of 12 foot 6-inch corrugated sections. The guard rails are spliced together by overlapping the ends of sections and securing them with eight securing bolts. Due to the corrugated curvature of the guard rail sections, the sections do not snugly mate when overlapped. This causes a problem due to the fact that the securing holes do not simultaneously align.
Heretofore, assembly has been accomplished by the use of a pointed pry bar inserted and twisted in a first set of holes forcing alignment of a second set of holes. This permits the insertion of a bolt in the second set of holes. This procedure is repeated until all of the securing bolts have been inserted.
One prior art device for holding a nut under a hole in corrugated building material is disclosed in the U.S. Pat. No. 2,935,314 of Ford. The Ford disclosure includes a base for fitting under the corrugated material and for holding the nut, a curved leg attached to the base, an arm pivotally attached to the leg at a point above the building material, a lever and link assembly pivotably attached to both the leg and the arm and a spring attached to the leg and the link for urging the link and arm toward the material maintaining the nut in position under the hole. Force on the lever is transmitted to the link opposing the spring and lifting the arm permitting insertion or removal of the material. Although useful in holding the nut in alignment, the clamping force afforded by the spring is insufficient to snugly mate sections of guard rail.